You may not live in a state that bases your child support obligation on a percentage of your income, because only nine states and the District of Columbia calculate support this way as of 2013: Wisconsin, Texas, North Dakota, New York, Nevada, Mississippi, Illinois, Arkansas and Alaska. This formula is called the percentage of obligor's income model, and it's the simplest equation for calculating a parent's support obligation.
Percentage of Obligor's Income Model
In its simplest form, the percentage of obligor's income model calculates support as an exact portion of the non-custodial parent's income. The portion increases with each additional child you are supporting. Some jurisdictions add subtle variations to this formula, so the percentage differs from state to state. For example, in Mississippi, it's 14 percent for one child. This increases to 17 percent for one child in Wisconsin, and in Illinois and Texas, it's 20 percent. This model doesn't give any weight to the custodial parent's income. It's based entirely on what the non-custodial parent earns. It typically does not take into consideration how much time your child spends with you – periods during which you support her directly. If you're also supporting children from another relationship, some states – such as Texas – will reduce the percentage to accommodate this.
The percentage is usually based on your net income. Most states that use this model consider your net income to be what remains after you pay mandatory taxes. Illinois and Texas allow you to also subtract the cost of union dues and Illinois courts may allow a deduction for health insurance. You must add together all your sources of income, however. For example, if you work a regular job and have a landscaping business on the side, or if you collect income from some strategic investments, these other sources of money count toward your child support as well.
Courts reserve the right to deviate from child support guidelines – the percentage of child support dictated by law. Typically, they only do so under extraordinary circumstances. For example, if your child has special needs, the percentage might increase. If your teenager has a very good job of his own, a judge can take this into consideration and may lower your percentage. Judges decide these matters on a case-by-case basis.
Income Shares Model
The other 41 states use a much more complicated formula when calculating support. The income shares method uses both parents' earnings based on the presumption that if the family were still intact, the children would enjoy the benefit of both incomes. After both incomes are added together, the court determines how much your income contributes to the total. For example, if you and your ex jointly earn $6,000 a month, and you're responsible for $4,500 of that total, your income represents 75 percent. State law determines how much of the $6,000 total should be set aside for your children's clothing, shelter and food. If your state says that your child's needs require $1,000 a month of your joint incomes, your support obligation would be $750 – 75 percent of $1,000. The income shares model usually adds on costs for work-related child care and your child's medical needs. If these run $1,000 a month, you would have to pay 75 percent of $2,000, not $1,000. The income shares model can be adjusted to allow for how much time your child spends with you.